On Thu, Sep 21, 2017 at 3:58 AM, Daniel Santos <daniel.san...@pobox.com> wrote: > On 09/19/2017 01:58 AM, Jakub Jelinek wrote: >> What can be done in libgcc is detect in configure whether the assembler >> supports AVX, and if not, provide some alternative (e.g. because the insns >> are always the same, you could just code them as .byte or something similar). >> >> Say like: >> --- i386-asm.h 2017-09-18 18:34:30.917126996 +0200 >> +++ i386-asm.h 2017-09-19 08:56:58.829559038 +0200 >> @@ -70,6 +70,7 @@ ASMNAME(fn): >> #ifdef MS2SYSV_STUB_AVX >> # define MS2SYSV_STUB_PREFIX __avx_ >> # define MOVAPS vmovaps >> +# define BYTE .byte >> #elif defined(MS2SYSV_STUB_SSE) >> # define MS2SYSV_STUB_PREFIX __sse_ >> # define MOVAPS movaps >> @@ -84,7 +85,8 @@ ASMNAME(fn): >> FUNC_END(PASTE2(MS2SYSV_STUB_PREFIX, base_name)) >> >> /* Save SSE registers 6-15. off is the offset of rax to get to xmm6. */ >> -# define SSE_SAVE \ >> +# ifdef HAVE_AS_AVX > > I'm not exactly an autotools expert, but libtim defines HAVE_AS_AVX from > libitm/acinclude.m4 -- of course I need it in libgcc. Similarly, gcc > has a nice generic gcc_GAS_CHECK_FEATURE macro in gcc/acinclude.m4 which > it uses for all of its HAVE_AS_* macro tests defined in > gcc/configure.ac. I can just copy, paste and edit what's in libitm, but > I find that rather distasteful. Is there a cleaner way to do this? Can > I suck gcc_GAS_CHECK_FEATURE and it's deps out of gcc/acinclude.m4 and > put it somewhere central, like config/as.m4? The upside would be the > ability to make HAVE_AS_* macros in other sub-projects more uniform. > > Alternatively, I can just do the copy and paste and deal with it -- it's > not that much code. :) > > Also, is there any sense in doing this same check for SSE support in the > assembler? It's been out for 18 years now.
binutils 2.13.1 are required to buld the compiler on i?86-*-linux*, so I guess SSE support is assumed. Uros.
